1. Technical Field
The present invention is directed toward brakes for bicycles, and more particularly toward a bicycle brake lever that is adjustable to vary the leverage applied to a bicycle brake connected to the lever by a brake cable.
2. Background Art
Bicycle brakes can broadly be classified as handle bar brakes and pedal brakes, depending upon the location where a rider actuates the brakes. As the names suggest, handle bar brakes are actuated at the bicycle handle bar by a rider squeezing a gripping bar of a brake lever assembly against the handle bar with his hands, and pedal brakes are actuated at the bicycle pedals. The present invention is an improvement to handle bar brakes.
Numerous types of bicycle brake mechanisms are known in the art, including drum brakes, cantilever brakes, disk brakes and calliper brakes. One common feature of these brake mechanisms is that the braking force is a function of the force applied to a brake cable extending between the brake mechanism and a brake lever assembly.
Typically a brake lever assembly consists of a brake handle including a finger grip bar and a transverse mounting arm. The mounting arm is attached to the bicycle handle bars by a mounting bracket for pivotal movement relative to the mounting bracket about a fixed axis. The brake cable is attached to the mounting arm a select distance from the fixed axis. As the finger grip bar is squeezed by a rider, the mounting arm pivots, increasing the tension on the brake cable, thereby actuating the brake mechanism. Once the brake mechanism is adjusted, the braking force is a function of how hard the finger grip bar is squeezed. How hard the finger grip must be squeezed and how far it must travel to provide a given braking force is known as the "feel" of the brakes.
Bicyclists, particularly avid bicyclists, each have a preferred feel for their bicycle brakes. Riders tend to anticipate the braking force that will result based upon the feel of their brakes. This feel is particularly important in high performance bicycling, such as off the road mountain biking, where applying too much braking force under certain conditions can cause the wheels to lock, resulting in a potentially dangerous loss of rider control or too little braking force can have disastrous consequences. Thus, not only is a particular feel a matter of user preference, in performance situations a consistent feel contributes to rider safety. To complicate matters, as brake pads wear, the feel of brakes can vary during a ride, particularly during off the road biking where dirt and grit increase brake pad wear and where brakes must be used often and aggressively.
With a conventional brake lever assembly, in order for a bicyclist to obtain desired feel for the handle bar brakes, the brake mechanism itself must be adjusted. This is a time consuming and difficult process requiring special tools. Adjustments are particularly difficult under field conditions where a bicyclist either does not have the necessary tools or does not want to take the time to adjust the brake mechanism.
An alternative to adjustment to the brake mechanism to alter the brake feel known in the art is providing a structure in the brake lever assembly for varying the distance between the fixed axis and the point of attachment of the brake cable to the mounting arm. This distance is known as the pivot arm. The known prior art device provides a plurality of holes along the length of the mounting arm at various distances from the fixed axis. While this structure does provide for coarse adjustment of the brake feel, the adjustment is only between pre-selected distances between the fixed axis and the point of attachment of the brake cable. Thus, only a limited number of pivot arm distances and therefore brake feels, are available. In addition, while this structure does not require disassembly of the brake mechanism to adjust the brake feel, it does require disassembly of the brake lever assembly to reposition the point of attachment of the brake cable to the mounting arm. Thus, adjustment of the brake feel with this structure is still time consuming and requires tools which might not be available under field conditions.
The present invention is directed toward overcoming one or more of the problems discussed above.